Method of making double walled articles and the like



Jan. 6, 1942. w. H. KLOCKE 2,269,313 METHOD OF MAKING DOUBLE WALLEDARTICLES AND THE LIKE 3 Sheets-Sheet 1 Filed Feb. 10, 1940 9% ATTORNEYS?f r 2 M m f fi m i, F a .r w w 1 u Jan. 1942. w. H. KLOCKE METHOD, OFMAKING DOUBLE WALLED ARTICLES'AND THE, LIKE 3 Sheets-Sheet 2 Filed Feb.10, 1940 i 5 mm INVENTOR. W/LL/ M H. KLOGKE BY ATTORNEYS.

5 Sheets-Sheet 3 Fig. 10

- HQVENTOR. \A/IL L-IAM H. /(LOCKE fijM M 6 ATTORNEYS? Jan. 6, 1942.

w. H. KLOCKE METHOD OF MAKING DOUBLE WALLED ARTIGLES'AND THE LIKE FiledFeb. 10, 1940 -duced in commercia tively low cost.

.cles; r Fig.2 is a view similar to Fig. 1,=but showing 1 drawingoperation;

' Fig. 3 is a viewsimilar the drawn article about to Patented J an. 6, 1942 oFFIcE METHOD or MAKINGDOUBLEW LLED narrows ANDTHE LIKE William H.Klocke woodhaven, N; Y., assignor to E. W. Bliss (iom'pan'yt B ration ofDelaware This invention relates to a novel methodpf makingdouble-walled'articles and ;thelike.; d

In the manufacture of double-walledj articles, such as bathtubs,broilers, roasters, lampsockets,

' munition shells, and the like, it has heretofore g been customary todraw, ablank to "provide a cup-shaped portion and aflange extendingoutwardly from such cup-shaped portion, andilihen, by a redrawingoperation, involvin the useoi a drawing punch, move; said' cup-shapedportion g Such a manner as to aw aid flangerinto a second wall, parallelwithth wall Qf'saidcuw h ped portion.

- 'Ifhis practice resultsin thesettingupofaconsiderable friction betweenthe'blank and .the noses l of the drawing punch; resulting in thisportion of the punch;

It is a primary object of the present invention to provideia novelmethod of, making articles of the aforesaid character, whereby thefriction be-g g ,A further object of the invention is to provide a novelpress which is particularly adapted' foimg -;the practice of theaforesaid'method. I

A still further object of the invention is to, provide a novelarrangement of press parts, whereby articles of the aforesaid charactercanbe .pro-

lly; large: quantities at "rela 3 To; the accomplishmentipi :theforegoing and related ends; said invention, then, consists of the Imeansand steps hereinafter fully describedand particularly pointed outin the claim; the .-an- ;35 is mountedfor reciprocal movement in theopen- -nexed drawings and the following description setting forth indetail certain means and one -mode of carrying out the invention, suchdisclosed means andgmode illustrating hoWever,'-but one of various waysin which the-principle of the press parts, and showing a blank'inposition to be subjected to a drawingoperation by a method l commonly'used for making double-walled artithe parts of the pressat' theconclusion ofthe 23'') to Fig; lfb'ut showing "be subjected to are--drawing operation;

Fig. 4 isa view s'imilarto Fig. 3, butshowingv the parts oi thepress atthe conclusion of the? redrawing operation; I Fig. 5 is across-sectional view of the finished article resulting from the methodillustrated in Figs. 1 to 4, inclusive;

Fig. 6 is a view of press parts embodying the i? novel feature oftheinvention, and showing a -drawn-article about to be subject to theredraw- H ing operation by the method of the present invention; v Fig."7 is a view similar to Fig. 6, but showing the press partsattheconclusion of'the redraw- ,ing operation; y 1

Fig 8 is a cross-sectional view of the finished h article resulting fromthe methodillustrated in ,Figs. 1, 2,6 and 7; q I a Fig. 9 is a frontelevation of a toggle press which is'adapted for the practice of theredrawing operation of-the present invention;

Fig. 10 is a side elevationalview of the press 5 shownin Fig. 9;

Fig. "11 isa fragmentary vertical cross-sectional view,-taken' on theline I l--H of--Fig-. 9;

Fig. 12 is a fragmentary vertical cross-sec- Otionalview, taken on theline l2 l2- of Fig. 9.

Referring 'more particularly to Figs. 1 to 5 i inclusive, whichillustrate a;method commonly used fofmaking double-walled articles,such, for ..example, asbathtubs, broilers, munition shells, 5 etc, ablankl,- of any desired contounand used, ,fin thisv instance,for-producing a shell, is placed upon ardie Zhaving a central opening 3,within which a knockout member 4 ismounted for re- I ciprocal movement.The blank'l? is preliminar- 0 lly clamped to the upper surface of thedie 2 by means of a blank holderihavinga central opening 6, which issmaller'in its dimensions than the ;opening by an amount substantiallyequal to twice the thickness 'Off the blank I A punch l ing Got theblank holder, said punch conforming in its *externalcontour to thecontour of the i opening With the blank and press parts positioned, as

0. shown in Fig. 1, the punch 1 and knock-out member 4 are caused a to;simultaneously descend tojthe position shown in Fig. 2, as a result ofwhich theblank hasimparted thereto" the cupl, shaped form shown inFig.2, consisting of a bottomorbase la, aside wall lb,-and an outwardlyextending flange lc, which lies in a planeparallelwith the bottom la.

The drawn shell is then placed in another pressjint'an' inverted?position, as shown in Fig. 3, fl'with'the :flange': lc resting on a'die8, similar to smthe'die 2 ;tand having an opening 9. in which a combinedknockout and pressure pad member In ismounted 'forreciprocal movement.The mem- .ber10 has a portion II which supports theradia'lly'i'nwar'dportion ofthe'fiange l0, and a portion l2 of smaller diameter whichextends into the shell and engages the inner. surface of the wall lb ofthe shell. The shell is clamped to the die 8 by means of a blank holderI3 having an 1) opening H in which a punch 15 is mounted for reciprocalmovement. The punch is made hollow for the reception of the shell, andhas a. cylindrical body portion I5a, which is interposed between theblank holder I3 and the wall lb of the shell, and engages the flange Icof the shell.

With the shell and press thus positioned, the member I and punch I5 arecaused to move-to the position shown in Fig. 4, therebywithdrawing theflange Ic of the shell from the space between the die 8 and holder I3andIorming therefrom a flange or second wall Id, which is spaced from butparallel with the wall lb of the wall. Following this redrawingoperation, the punch is elevated, and the finished shell, as shown inFig. 5, knocked out of the die 8 by means of the stripping action of themember II].

It has been found that as a result of manufacturing shells by theforegoing method, that con siderable friction is set up betweenthe'shell and the nose b of the punch, resulting in rapid wear of thisportion of the punch. v

The redrawing operation, in accordance "with the present invention, asillustrated more or less diagrammatically in Figs. 6, 7 and 8,eliminates the wear of the nose of the punch, thereby increasing thelife of the punch. v

' In accordance with the new method, the blank is firstformed to:provide a drawing shell in the manner shown in Figs. 1 and 2.Thereafter; the drawn shell, instead of being inverted, as" in 'the oldredrawing operation, is placed, as shown in Fig. 6, with its flange Icresting on a Marquette pressure pad I6. Such a pressure pad is usuallysupported on plungers 'II, which extend through 'for maintaining saidpad in elevated position being shown in the form of a pneumaticallyoperated ram 24 carrying a cross-plate 25, to which the plungers H whichsupport the pad are secured. Mounted centrally of the bed I8 is the dieI9.

The press further includes housings or uprights 26 and 21 provided withgibs 28 in which is slidably mounted a holder 29 for the drawing punch20. The holder 29 is pivotally connected as at 30 to links 3|, the upperends of which are pivotally connected to the main drive shaft 32'of thepress, in eccentric relation to the axis of the latter. I

'Ihe'shaft'32 is journalled in the uprights 26 and 21, and has securedto one end thereof a crank 33, which is pivotally secured at its outerend to an outside connection-34. The connection'34 is pivoted, as at 35,to a cross-head 36 mounted for vertical sliding movement on a guide 31aflixed to the press.

'Pivotally secured, as at 38 and 39, to the upper end of the cross-head36 are links 40,'the upper ends of which are pivoted to rock shafts 4 I,which are journalled in the crown 42 of the press. The rockshafts M areprovided centrally thereof with ears or lugs 43, to the outer ends ofwhich are pivoted toggle links 44. The links 44 are pivotally'connecte dat their lower ends to a openings in the bolster-or bed I8 of the press,

and are adapted to be normally maintained in elevated position bypneumatic'means. 'The'bed I8 of the press carries a die I9, in which thebottom Ia and wall Ib of the shell are disposed, the nose Id of the dieengaging the radially innermost portion of the flange I of the shell.The flange I0 is, in this case, clamped to the pad I6 by means of adrawing punch 20 having an opening 2I which is larger in its dimensionsthanthe external diameter of the nose Id by an amount substantiallyequal to twice the thickness of the metal of the shell.

Clampingthe bottom Ia and lb of "the shell to the die I9 is a blankholder punch 22.

With the parts thus positioned, the punch 20 and pad I6 arecaused'todescen'd to the position shown inFig. '7, thereby causing theflange Ic to be withdrawn from the space between "the punch and pad andforming therefrom aflange, or second wall I'd, which is spaced from butparallel with the wall-Ib of the shell. Following this redrawingoperation, the finished shell, as illustrated in Fig. 8, is re'movedfrom the'pr'ess.

- It has beenfoundthat as a resultof redrawing the shell bytheoperationdepicted in Figs. 6 and'7, that friction ofth n'os'e Id of' the die I9is eliminated, with a'resultant increase in the life of the die.

The present elements illustrated in Figs. 6

and? may be incorporated in" either a' mechani cally .or hydraulicallyactuated press, but are preferably incorporatedin a double actiontoggle-drawing press, as shown in Figs. 9, 10, 11

and 12, since this involves a minimum amount- -of modification of astandard toggle-drawing 7o ter portion. press.

yoke 45, which extends from the front to the rear of "the press.

The yoke '45 carries a socket 46, which by means of a screw 41, isadjustable relatively to the yoke. The socket 46 has secured to itslower end, as by means of a set screw 48, the'stem 49 ofthe blank holderpunch 22.

The connections, in an actual press, have been so adjusted as to securea stroke of eight inches for the punch 22 and a stroke of four andonehalf inches for thedrawing punch 20.

Although I have described a toggle press as best embodying theprinciples of the invention, it will'b'e understoodthat they may also beembodied orincorporated in a hydraulic press.

Other'forms may be employed embodying the features of my inventioninstead of the one herein explained, change being made as regards themeans herein disclosed, provided the means stated by the following claimor the equivalent of such stated means be employed.

Itherefore particularly pointout and distinctly claim as my invention:

In a method of making-deep drawn, "doublewalled articles, the steps ofclamping the rim of a'bl'ankbetween a die and a blank holder, drawingthe center portion of the blank into said die by means of a punch,clamping said drawn center portion between a die and a blank holderpunch and clamping the'rim of the blank bepunch 'while" in clampingengagement with said rim to completely draw said rimabout saidsecond-named die into substantiallyparallel relation with thewall of theaforesaid drawn cen- KLOCKE.

